Switch-stand



W. A. BOGK.

SWITCH STAND.

(No Model.)

No. 437,966. Patented Oct. 7, 1890.

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UNITED STATES PATENT OFFICE.

WILLIAM A. BOOK, OF CHICAGO, ILLINOIS.

SWITCH-STAN D.

SPECIFICATION forming part of Letters Patent No.7437,966, dated October 7, 1890.

Application filed April 28, 1890.

To all whom it may concern:

Be it known that I, WILLIAM A. BOOK, of Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Switch-Stands, of which the following is a specification.

My invention relates chiefly to automatic or safety switch-stands which allow the switchrails to yield to a passing car-wheel in case they have not been properly set beforehand, thus preventing derailment or breakage; but it is in some of its parts applicable to rigid stands, as will appear.

The object of my invention is to increase the durability and ease of working of the 7 switch under ordinary circumstances by diminishing the number and weight of the moving parts and to diminish the liability of the stand to clog by the accumulation of ice and snow.

In the accompanying drawings, Figure l is a side elevation of my improved stand. Fig. 2 is a vertical section, and Fig. 3 a plan view, of the same. Figs. at and 5 are views of the locking-block and the cap, respectively.

The frame of the stand, as herein shown, consists of a hollow cylindrical casting A, having feet B B, by which it is secured to the ties in the usual manner. Instead of having two feet, it may have a single foot adapted to fasten to one tie only as other stands are sometimesarranged, and the frame may be changed in other ways without departing from the essential features of my invention.

Through the frame passes the shaft 0, having at its lower end the crank-arm D, to which the switch-rod E is connected in the ordinary manner.

Upon the shaft 0 above the frame is keyed or otherwise fastened the block F, to which the hand-lever G is pivoted.

Between the block F and the frame A is interposed the cap H, the lower end of which is fitted to the cylindrical top of the frame and the upper end to the block F. The outside of the block F and the upper part of the cap H are squared to the same size, and the forked end g of the hand-lever G fits the squared parts snugly. Instead of being squared, the cap and block may be shaped to any other polygonal section and the lever fitted thereto 5 but the squared shape is in all Serial No. 349,780. (No model.)

respects The pivotal point of the lever G is so located in the lever G and in relation to the dividing line between the block F and cap H that when the handle is down, as shown in full lines in the drawings, the forked end g embraces the squared end of the cap H, preferably extending somewhat above the cap Hto include the lower part of the block, so that the cap and block are rigidly locked together.

When in this position, the lever G may besecured by a lock inserted in the lug f of the block F. When the lever G is raised to the position shown in dotted lines in Fig. 1, the forked end is wholly above the cap H, and the block F may therefore turn, and with it the shaft 0, independently of the cap.

Fitted within the frame A in such a manner as to prevent its revolving, but not to prevent its free longitudinal movement, is a block J, which may be designated as a locking-block. Its preferred shape is shown in Figs. 2 and 4:. It may be described in a general way as having a prismatic body and a pyramidal top, preferably the corners of both body and top being rounded and the sides being hollowed. The top j of the block J fits a corresponding hollow h in the bottom of the cap H, the hollow being shown in Fig. 5. The block J is held in contact with the cap by the pressure of a spring K, Fig. 2, surrounding the shaft 0 and resting on the frame A. The block J thus serves as a yielding lock for the cap H and the frame of the switch-stand. The shape given the lockingblock J, as just described, is such that a pressure tending to turn the cap He. g., such as would be caused by a car-wheel passing over the point-rails when not properly set-will tend to depress and will depress the block J. The resistance will be considerably greater at the beginning than when the revolution of the switch;shaft G has been partly effected, and when the rails have been moved a little more than half their throw by the car-wheel the tendency of the stand will be to complete the shifting. The resistance of the lockingblock is easily gaged independently of the spring K by making the slant of the pyramidal top greater or less. Thus a compreferable, and Itherefore adopt it.

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a secure lock.

The slanting pyramidal top of the block and the corresponding cavity of the cap form clutch surfaces, which by reason of their slope in a radial direction from the shaft 0 have several advantages over the clutches ordinarily used, one advantage being the fact just mentioned, that the resistance to the turning of the shaft 0 diminishes after its movement has once begun, so that a strong resistance to the accidental m vement of the switch may be provided without impairing the facility with which the switch is thrown by the passage of a car through it. Other advantages are that longer bearing-surfaces are obtainable in the same diameter of clutch, as the hypotenuse of a triangle is longer than its base, (see Fig. 2,) and a lighter and more elastic spring may be used.

There being no exposed cavities or recesses on the exterior of the stand which by filling up can interfere with the releasing of the hand-lever or the operation of the switchstand, the clogging with snow and ice, so annoying and productive of delay in the winter, is avoided. Only the lever G has to be moved to release the stand for operation by hand. Hence the switch is easily operated. The bearing-surfaces are few and present a large area, durability and freedom from lost motion being thereby assured.

There is a special utility in the combination of the lever G with the squared cap H, because the lever will lock on any of the squared faces of the cap, so that if the cap be turned by the running of a car through the switch it is not necessary to turn the cap back to its original position; but the lever G may also be used in a rigid stand having its top squared, substantially as if cap G should be made a part of the frame, and I contemplate such use as within my invention.

I claim- 1. The combination, in a switch-stand, of a frame, a shaft revoluble in said frame adapted to operate the switch, a block of polygonal section secured to said shaft, a hand-lever having a forked end fitted to said block, a

cap interposed between said block and frame having a top of like section as said block over which the forked end of said lever extends when the lever is lowered, a prismatic block fitted within said frame and having a pyramidal top fitted to a corresponding cavity in said cap, and a spring for maintaining contact between said last-named block and cap, substantially as described.

2, In a switch-stand, the combination of a frame, a shaft revoluble therein and adapted to operate the switch,the top upon said frame being of polygonal section, a block secured to said shaft and corresponding in section to said top, anda forked lever adapted to fit said top and block and pivoted to the latter, substantially as described.

3. In a switch-stand, the combination of a frame, a shaft revoluble therein and adapt-ed to operate the switch, a block secured to said shaft and provided with a hand-lever, a cap fitted between said block and frame and adapted to be locked to said shaft by said hand-lever, and a spring-actuated block fitted within said frame, having a pyramidal top fitted to a corresponding cavity in the cap, substantially as described.

4 In a switch-stand, the combination of a frame,a shaft revoluble therein and adapted to operate the switch, a cap fitted to said frame and encircling said shaft, devices adapted to lockin g said cap to said shaft, a locking-block fitted to slide but not to revolve in said frame, so as to be movable longitudinally of the shaft but not to revolve, and having a pyramidal top fitting a corresponding cavity in said cap, and a spring adapted to maintain contact between said cap and locking-block, substantially as described.

WILLIAM A. BOOK. Witnesses: IRWIN VEEDER,

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